2-(Substituted benzoyl)-4-(substituted or unsubstituted phenyl)-1,3-cyclohexanediones as herbicides

ABSTRACT

Compounds of the formula ##STR1## wherein R is halogen; C 1  -C 2  alkyl; C 1  -C 2  alkoxy; trifluoromethoxy or difluoromethoxy; nitro; cyano; C 1  -C 2  haloalkyl; R a  SO n  --wherein n is 0 or 2 and R a  is C 1  -C 2  alkyl, trifluoromethyl or difluoromethyl; 
     R 1  is hydrogen or C 1  -C 4  alkyl; 
     R 2  is hydrogen or C 1  -C 4  alkyl; or 
     R 1  and R 2  together are C 2  -C 5  alkylene; 
     R 3  is hydrogen or C 1  -C 4  alkyl; 
     R 4  is hydrogen or C 1  -C 4  alkyl; or 
     R 3  and R 4  together are C 2  -C 5  alkylene; 
     R 5 , R 6 , R 7  and R 8  independently are (1) hydrogen; (2) halogen; (3) C 1  -C 4  alkyl; (4) C 1  -C 4  alkoxy; (5) trifluoromethoxy; (6) cyano; (7) nitro; (8) C 1  -C 4  haloalkyl; (9) R b  SO n  -- wherein n is the integer 0, 1 or 2; and R b  is (a) C 1  -C 4  alkyl; (b) C 1  -C 4  alkyl substituted with halogen or cyano; (c) phenyl; or (d) benzyl; (10) --NR c  R d  wherein R c  and R d  independently are hydrogen or C 1  -C 4  alkyl; (11) R e  C(O)-- wherein R e  is C 1  -C 4  alkyl or C 1  -C 4  alkoxy; or (12) --SO 2  NR c  R d  wherein R c  and R d  are as defined; and (13)  --N(R c )C(O)R d  wherein R c  and R d  are as defined; and 
     R 9  is hydrogen or C 1  -C 4  alkyl, and their salts.

BACKGROUND OF THE INVENTION

U.S. Pat. No. 4,350,705 relates to certain antihypertensive compoundsthat can have the following structural formula ##STR2## wherein R¹ isunsubstituted or substituted phenyl; M is --(CH₂)_(m) in which m is theinteger 0-4; and X, Y and Z are hydrogen, lower alkyl, lower alkoxy,lower alkylcarbonyloxy, hydroxy, lower alkylsulfonyl, nitro, cyano orhalogen. Specifically taught are2-benzoyl-5-phenyl-cyclohexane-1,3-dione and2-(4-chlorobenzoyl)-5-phenylcyclohexane-1,3-dione.

DESCRIPTION OF THE INVENTION

This invention relates to 2-(substituted benzoyl)-4-(substituted orunsubstituted phenyl)-1,3-cyclohexanediones and their use as herbicides.

One embodiment of this invention is an herbicidal composition comprisingan herbicidally active 2-(substituted benzoyl)-4-(substituted orunsubstituted phenyl)-1,3-cyclohexanedione and an inert carriertherefor. The 5- and 6-positions of the 1,3-cyclohexanedione moiety arepreferably substituted with groups hereinafter defined, most preferablywith hydrogen or methyl groups. The benzoyl and phenyl moieties can besubstituted, preferably with the groups hereinafter recited.

Also embodied within the scope of this invention are novel compoundshaving the following structural formula ##STR3## wherein R is halogen;C₁ -C₂ alkyl, preferably methyl; C₁ -C₂ alkoxy, preferably methoxy,trifluoromethoxy or difluoromethoxy; nitro; cyano; C₁ -C₂ haloalkyl,preferably trifluoromethyl; R^(a) SO_(n) -- wherein n is 0 or 2,preferably 2 and R^(a) is C₁ -C₂ alkyl, preferably methyl,trifluoromethyl or difluoromethyl. Preferably, R is chlorine, bromine,C₁ -C₂ alkyl, C₁ -C₂ alkoxy, trifluoromethyl, cyano, nitro, C₁ -C₂alkylthio or C₁ -C₂ alkylsulfonyl; more preferably chlorine, nitro,methyl, trifluoromethyl or methylsulfonyl; and

R¹ is hydrogen or C₁ -C₄ alkyl, preferably methyl;

R² is hydrogen or C₁ -C₄ alkyl, preferably methyl; or

R¹ and R² together are C₂ -C₅ alkylene;

R³ is hydrogen or C₁ -C₄ alkyl, preferably methyl;

R⁴ is hydrogen or C₁ -C₄ alkyl, preferably methyl; or

R³ and R⁴ together are C₂ -C₅ alkylene;

R⁵, R⁶, R⁷ and R⁸ independently are (1) hydrogen; (2) halogen,preferably chlorine, fluorine or bromine; (3) C₁ -C₄ alkyl, preferablymethyl; (4) C₁ -C₄ alkoxy, preferably methoxy; (5) trifluoromethoxy; (6)cyano; (7) nitro; (8) C₁ -C₄ haloalkyl, more preferably trifluoromethyl;(9) R^(b) SO_(n) -- wherein n is the integer 0, 1 or 2, preferably 2;and

R^(b) is

(a) C₁ -C₄ alkyl, preferably methyl;

(b) C₁ -C₄ alkyl substituted with halogen or cyano, preferablychloromethyl, trifluoromethyl or cyanomethyl;

(c) phenyl; or

(d) benzyl;

(10) --NR^(c) R^(d) wherein R^(c) and R^(d) independently are hydrogenor C₁ -C₄ alkyl; (11) R^(e) C(O)-- wherein R^(e) is C₁ -C₄ alkyl or C₁-C₄ alkoxy; (12) --SO₂ NR^(c) R^(d) wherein R^(c) and R^(d) are asdefined; or (13) --N(R^(c))C(O)R^(d) wherein R^(e) and R^(d) are asdefined; and

R⁹ is hydrogen or C₁ -C₄ alkyl.

Preferably R⁵ is in the 3-position. More preferably R⁵ and R⁷ arehydrogen, chlorine, fluorine, trifluoromethyl, cyano, C₁ -C₄ alkoxy orC₁ -C₄ thioalkyl. Most preferably, R⁵ and R⁷ are hydrogen. Preferably R⁶and R⁸ are in the 4-position. Most preferably R⁶ and R⁸ are halogen,cyano, trifluoromethyl, or R^(b) SO₂ wherein R^(b) is C₁ -C₄ alkyl,preferably methyl or C₁ -C₄ haloalkyl, preferably chloromethyl,difluoromethyl or trifluoromethyl.

The term "C₁ -C₄ alkyl" includes methyl, ethyl, n-propyl, isopropyl,n-butyl, sec-butyl, isobutyl and t-butyl. The term "halogen" includeschlorine, bromine, iodine and fluorine. The terms "C₁ -C₄ alkoxy"includes methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy,isobutoxy and t-butoxy. The term "C₁ -C₄ haloalkyl" includes the alkylgroups defined above under C₁ -C₄ alkyl in which one or more hydrogensis replaced by chlorine, bromine, iodine or fluorine.

Salts of the above-described compounds (as defined hereinafter) areincluded within the scope of the instant invention.

The compounds of this invention can have the following four structuralformulae because of tautomerism: ##STR4## wherein R, R¹, R², R³, R⁴, R⁵,R⁶, R⁷, R⁸ and R⁹ are as defined above.

The circled proton on each of the four tautomers is reasonably labile.These protons are acidic and can be removed by reaction with a base toform a salt having an anion of the following four resonance forms:##STR5## wherein R, R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸ and R⁹ are as definedabove.

Examples of cations of these bases are inorganic cations such as alkalimetals, e.g. lithium, sodium and potassium; the alkaline earth metals,e.g. calcium and magnesium or ammonium or organic cations such assubstituted ammonium, sulfonium, sulfoxonium or phosphonium wherein thesubstituents are aliphatic or aromatic groups.

Those skilled in the art will recognize in considering the salts of thisinvention that varying degrees of association between the anion andcation will exist depending upon the nature of the cation. In someinstances with a suitable cation, such as copper, the salt can exist ina chelated form.

The compounds of this invention and their salts are active herbicides ofa general type. That is, they are herbicidally effective against a widerange of plant species. The method of controlling undesirable vegetationof the present invention comprises applying an herbicidally effectiveamount of the above-described compounds or their salts to the area wherecontrol is desired.

The compounds of the present invention can be prepared by the followingtwo-step general method.

The process proceeds via the production of an enol ester intermediate asshown in reaction (1). The final product is obtained by rearrangement ofthe enol ester as shown in reaction (2).

The process is conducted in the presence of a catalytic amount of asource of cyanide anion and/or hydrogen cyanide, together with a molarexcess, with respect to the enol ester, of a moderate base.

The two reactions may be conducted as separate steps by isolation andrecovery of the enol ester using conventional techniques prior toconducting step (2), or by addition of a cyanide source to the reactionmedium after the formation of the enol ester, or in one step byinclusion of the cyanide source at the start of reaction (1). ##STR6##wherein R through R⁹ and moderate base are as defined and X is halogen,preferably chlorine, C₁ -C₄ alkyl--C(O)--O--, C₁ -C₄ alkoxy--C(O)--O--or ##STR7## wherein, R, R⁵ and R⁶ in this portion of the molecule areidentical with those in the reactant shown above and the moderate baseis as defined, preferably tri-C₁ -C₆ alkylamine, alkali metal carbonateor alkali metal phosphate.

Generally, in step (1) mole amounts of the dione and substituted benzoylreactant are used, along with a mole amount or excess of the base. Thetwo reactants are combined in an organic solvent such as methylenechloride, toluene, ethyl acetate or dimethylformamide. The base orbenzoyl reactant preferably is added to the reaction mixture withcooling. The mixture is stirred at 0° C.-50° C. until the reaction issubstantially complete. ##STR8## wherein the moderate base and R throughR⁹ are as defined above.

Generally, in step (2) a mole of the enol ester intermediate is reactedwith 1 to 4 moles of the moderate base, preferably about 2 moles ofmoderate base and from 0.01 mole to about 0.5 mole or higher, preferablyabout 0.01-0.1 mole of the cyanide source. The mixture is stirred in areaction pot until the rearrangement is substantially complete at atemperature below 50° C., preferably about 20° C. to about 40° C., andthe desired product is recovered by conventional techniques.

The term "cyanide source" refers to a substance or substances whichunder the rearrangement conditions consists of or generates hydrogencyanide and/or cyanide anion.

Preferred cyanide sources are alkali metal cyanides such as sodium andpotassium cyanide; cyanohydrins of methyl alkyl ketones having from 1-4carbon atoms in the alkyl groups, such as acetone or methyl isobutylketone cyanohydrins; benzaldehyde cyanohydrin; cyanohydrins of C₂ -C₅aliphatic aldehydes such as acetaldehyde cyanohydrin, propionaldehydepropionaldehyde cyanohydrin, etc.; cyclohexanone cyanohydrin;lactonitrile; zinc cyanide; di- and tri-(lower alkyl) silyl cyanides,notably dimethyl- and trimethyl-silyl cyanide; potassium ferric cyanide;and hydrogen cyanide itself. Hydrogen cyanide is considered mostadvantageous as it produces relatively rapid reaction and isinexpensive. Among cyanohydrins the preferred cyanide source is acetonecyanohydrin.

The cyanide source is used in an amount up to about 50 mole percentbased on the enol ester. It may be used in as little as about 1 molepercent to produce an acceptable rate of reaction at about 40° C. on asmall scale. Larger scale reactions give more reproducible results withslightly higher catalyst levels of about 2 mole percent. Generally about1-10 mole % of the cyanide source is preferred.

The process is conducted with a molar excess, with respect to the enolester, of a moderate base. By the term "moderate base" is meant asubstance which acts as a base yet whose strength or activity as a baselies between that of strong bases such as hydroxides (which could causehydrolysis of the enol ester) and that of weak bases such asN,N-dimethylaniline (which would not function effectively). Moderatebases suitable for use in this embodiment include both organic bases,e.g., trialkylamines such as triethylamine and inorganic bases such asalkali metal carbonates and phosphates. Suitable inorganic bases includepotassium carbonate and trisodium phosphate.

The base is used in an amount of from about 1 to about 4 moles per moleof enol ester, preferably about 2 moles per mole.

When the cyanide source is an alkali metal cyanide, particularlypotassium cyanide, a phase transfer catalyst may be included in thereaction. Particularly suitable phase transfer catalysts are the crownethers.

A number of different solvents are useful in this process, depending onthe nature of the acid halide or the acylated product. A preferredsolvent for this reaction is 1,2-dichloroethane. Other solvents whichmay be employed, depending on the reactants or products include toluene,acetonitrile, methylene chloride, ethyl acetate, dimethylformamide, andmethyl isobutyl ketone (MIBK).

In general, depending on the nature of the reactants and the cyanidesource, the rearrangement may be conducted at temperatures up to about50° C.

The above described substituted benzoyl chlorides can be prepared fromthe corresponding substituted benzoic acids according to the teaching ofReagents for Organic Synthesis, Vol. I, L. F. Fieser and M. Fieser, pp.767-769 (1967). ##STR9## wherein R, R⁵ and R⁶ are as previously defined.

The substituted benzoic acids can be prepared by a wide variety ofgeneral methods according to the teaching of The Chemistry of CarboxylicAcids and Esters, S. Patai, editor, J. Wiley and Sons, New York, N.Y.(1969) and Survey of Organic Synthesis, C. A. Buehler and D. F. Pearson,J. Wiley and Sons, (1970).

The following are three representative examples of the methods describedtherein. ##STR10## wherein R, R⁵ and R⁶ are as previously defined.

In reaction (a) the substituted benzonitrile is heated to reflux inaqueous sulfuric acid for several hours. The mixture is cooled and thereaction product is isolated by conventional techniques. ##STR11##wherein R, R⁵ and R⁶ are as previously defined.

In reaction (b) the substituted acetophenone is heated to reflux forseveral hours in an aqueous hypochlorite solution. The mixture is cooledand the reaction product is isolated by conventional techniques.##STR12## wherein R, R⁵ and R⁶ are as previously defined.

In reaction (c) the substituted toluene is heated to reflux in anaqueous solution of potassium permanganate for several hours. Thesolution is then filtered and the reaction product is isolated byconventional techniques.

The above-described substituted cyclohexane-1,3-diones can be preparedaccording to the teaching of E. D. Bergmann and J. Szmuszkovicz, J.Amer. Chem. Soc., 875, 3226 (1953).

The following example teaches the synthesis of a representative compoundof this invention.

EXAMPLE 14-(2-Fluorophenyl)-2-(2-trifluoromethylbenzoyl)-cyclohexane-1,3-dione##STR13##

2-Trifluoromethylbenzoyl chloride (7.1 g, 0.034 mole) and4-(2-fluorophenyl)-1,3-cyclohexanedione (7.0 g, 0.034 mole) weredissolved in methylene chloride. Triethylamine (4.1 g, 0.041 mole) wasadded dropwise and the resulting solution stirred for one hour. Thesolution was washed with 2 normal hydrochloric acid (2N HCl), 5%potassium carbonate solution, and saturated sodium chloride solution,dried over anhydrous magnesium sulfate (MgSO₄) and concentrated undervacuum. The residue was dissolved in 40 ml of acetonitrile.Triethylamine (1 equivalent) and acetone cyanohydrin (0.4 ml) were addedand the solution stirred for 1 hour at room temperature. After dilutionwith ether (150 ml), the solution was washed with 2N HCl. The etherlayer was then stirred with 100 ml of 5% copper (II) acetate. Theresulting copper salt was filtered, washed with hexane, and stirred with6N hydrochloric acid to destroy the salt. The acidic aqueous solutionwas extracted with ether. The ether solution was then washed with waterand dried over MgSO₄. Concentration of the ether solution under vacuumafforded 4.4 g of the desired product as a brown oil (34.2% yield). Thestructure was confirmed by instrumental analysis.

The following is a table of certain selected compounds that arepreparable according to the procedure described hereto. Compound numbersare assigned to each compound and are used throughout the remainder ofthe application.

                                      TABLE I                                     __________________________________________________________________________     ##STR14##                                                                    Cmpd.                                                                         No. R  R.sup.1                                                                          R.sup.2                                                                         R.sup.3                                                                          R.sup.4                                                                         R.sup.5                                                                          R.sup.6                                                                            R.sup.7                                                                           R.sup.8                                                                           R.sup.9                                                                          m.p. °C.                           __________________________________________________________________________     1  Cl H  H H  H H  4-Cl H   H   H  139-140                                    2  Cl H  H H  H H  4-SO.sub.2 Me                                                                      H   3-CF.sub.3                                                                        H  glass                                      3  NO.sub.2                                                                         H  H H  H H  4-CF.sub.3                                                                         H   3-CF.sub.3                                                                        H  oil                                        4  Cl H  H H  H H  4-SO.sub.2 Me                                                                      2-F H   H  oil                                        5a CF.sub.3                                                                         H  H H  H H  H    2-F H   H  oil                                        6  Cl H  H H  H H  4-Cl 2-F H   H  oil                                        7  Cl H  H H  H H  4-Cl H   4-F H  oil                                        8  CH.sub.3                                                                         H  H H  H H  4-SO.sub.2 Et                                                                      2-F H   H  glass                                      9  CH.sub.3                                                                         H  H H  H H  4-SO.sub.2 Et                                                                      H   4-F H  oil                                       10  Cl H  H H  H H  4-SO.sub.2 Me                                                                      2-Cl                                                                              H   H  glass                                     11  Cl H  H H  H H  4-SO.sub.2 Me                                                                      2-MeO                                                                             H   H  135-140                                   12  Cl H  H H  H H  4-SO.sub.2 Me                                                                      2-F 6-Cl                                                                              H  94-98                                     13  Cl H  H H  H H  4-SO.sub.2 Me                                                                      H   4-MeO                                                                             H  glass                                     14  Cl H  H Me H H  4-SO.sub.2 Me                                                                      2-F H   H  glass                                     15  Cl H  H H  H H  4-SO.sub.2 Me                                                                      2-F H   Me glass                                     16  Cl Me H H  H H  4-SO.sub.2 Me                                                                      2-F H   H  75-80                                     17  NO.sub.2                                                                         H  H H  H H  4-Cl 2-F H   Me oil                                       18  NO.sub.2                                                                         H  H H  H H  4-Cl H   4-F H  oil                                       19  NO.sub.2                                                                         H  H H  H H  4-Cl H   3-CF.sub.3                                                                        H  oil                                       20  NO.sub.2                                                                         H  H Me H H  4-Cl 2-F H   H  glass                                     21  NO.sub.2                                                                         H  H H  H H  4-Cl 2-F 6-Cl                                                                              H  glass                                     22  NO.sub.2                                                                         Me H H  H H  4-Cl 2-F H   H  oil                                       23  NO.sub.2                                                                         H  H H  H H  4-Cl 2-Cl                                                                              H   H  172-175                                   24  Cl H  H H  H H  4-SO.sub.2 Me                                                                      H   H   H  oil                                       25  Cl H  H Me H H  4-SO.sub.2 Me                                                                      H   H   H  oil                                       26  CH.sub.3                                                                         H  H H  H H  4-SO.sub.2 Et                                                                      2-F H   Me oil                                       27  Cl H  H H  H H  4-SO.sub.2 Me                                                                      2-F 6-Cl                                                                              Me oil                                       28  Cl H  H Me H H  4-SO.sub.2 Me                                                                      H   H   Me oil                                       29  Cl H  H H  H H  4-SO.sub.2 Me                                                                      H   H   Me oil                                       30  NO.sub.2                                                                         H  H H  H H  4-CF.sub.3                                                                         2-F H   Me oil                                       31  NO.sub.2                                                                         H  H H  H H  4-Cl H   H   H  oil                                       32  NO.sub.2                                                                         H  H Me H H  4-Cl H   H   H  oil                                       33  Cl H  H H  H H  4-SO.sub.2 Me                                                                      2-Cl                                                                              4-Cl                                                                              H  oil                                       34  NO.sub.2                                                                         H  H Me H H  4-Cl H   H   Me oil                                       35  NO.sub.2                                                                         H  H H  H H  4-Cl H   H   Me oil                                       36  Cl H  H H  H 3-Cl                                                                             4-SO.sub.2 Et                                                                      2-F H   Me wax                                       37  NO.sub.2                                                                         H  H H  H H  4-CF.sub.3                                                                         H   H   H  oil                                       38  NO.sub.2                                                                         H  H H  H H  4-CF.sub.3                                                                         2-F H   H  oil                                       39  Cl Me H H  H H  4-SO.sub.2 Me                                                                      2-F H   Me oil                                       40  NO.sub.2                                                                         H  H H  H H  4-Cl 2-F H   H  oil                                       41  NO.sub.2                                                                         H  H H  H H  4-CF.sub.3                                                                         H   4-F H  oil                                       42  NO.sub.2                                                                         H  H H  H H  4-CF.sub.3                                                                         2-F 6-Cl                                                                              H  oil                                       43  NO.sub.2                                                                         H  H H  H H  4-CF.sub.3                                                                         2-NO.sub.2                                                                        H   H  oil                                       __________________________________________________________________________     a Prepared in Example I.                                                 

Herbicidal Screening Tests

As previously mentioned, the herein described compounds produced in theabove-described manner are phytotoxic compounds which are useful andvaluable in controlling various plant species. Selected compounds ofthis invention were tested as herbicides in the following manner.

Pre-emergence herbicide test. On the day preceding treatment, seeds ofseven different weed species are planted in loamy sand soil inindividual rows using one species per row across the width of a flat.The seeds used are green foxtail (FT) (Setaria viridis), watergrass (WG)(Echinochloa crusgalli), wild oat (WO) (Avena fatua), annualmorningglory (AMG) (Ipomoea lacunosa), velvetleaf (VL) (Abutilontheophrasti), Indian mustard (MD) (Brassica juncea), and yellow nutsedge(YNG) (Cyperus esculentus). Ample seeds are planted to give about 20 to40 seedlings per row, after emergence, depending upon the size of theplants.

Using an analytical balance, 600 milligrams (mg) of the compound to betested are weighed out on a piece of glassine weighing paper. The paperand compound are placed in a 60 milliliter (ml) wide-mouth clear bottleand dissolved in 45 ml of acetone or substituted solvent. Eighteen ml ofthis solution are transferred to a 60 ml wide-mouth clear bottle anddiluted with 22 ml of a water and acetone mixture (19:1) containingenough polyoxyethylene sorbitan monolaurate emulsifier to give a finalsolution of 0.5% (v/v). The solution is then sprayed on a seeded flat ona linear spray table calibrated to deliver 80 gallons per acre (748L/ha). The application rate is 4 lb/acre (4.48 Kg/ha).

After treatment, the flats are placed in the greenhouse at a temperatureof 70° to 80° F. and watered by sprinkling. Two weeks after treatment,the degree of injury or control is determined by comparison withuntreated check plants of the same age. The injury rating from 0 to 100%is recorded for each species as percent control with 0% representing noinjury and 100% representing complete control.

The results of the tests are shown in the following Table II.

                  TABLE II                                                        ______________________________________                                        Pre-Emergence Herbicidal Activity                                             Application Rate - 4.48 kg/ha                                                 Cmpd.                                                                         No.   FT     WG      WO    AMG   VL    MD    YNG                              ______________________________________                                        1     0      20      10    5     0     0     60                               2     0      75      60    80    95    100   70                               3     0      0       5     10    80    90    0                                4     95     100     90    100   100   100   80                               5     10     5       20    5     40    90    --                               6     0      10      10    40    100   100   60                               7     0      0       10    40    100   100   80                               8     30     100     85    95    100   100   80                               9     20     100     80    90    100   100   80                               10    85     100     80    80    100   100   80                               11    0      100     5     0     10    100   --                               12    100    100     10    50    100   100   80                               13    40     100     10    30    100   100   80                               14    100    100     80    100   100   100   80                               15    30     95      80    95    100   100   80                               16    90     100     30    100   100   100   80                               17    95     100     70    100   100   100   80                               18    100    100     70    100   100   100   80                               19    10     0       0     30    100   100   0                                20    50     80      40    100   100   100   75                               21    100    80      50    100   100   100   75                               22    10     85      40    100   100   100   70                               23    100    95      90    30    100   100   30                               24    100    100     90    100   100   100   80                               25    20     90      40    85    90    100   80                               26    0      70      30    90    100   100   80                               27    100    100     60    100   100   100   80                               28    0      80      10    90    100   100   80                               29    80     100     95    100   100   100   80                               30    100    100     90    100   100   100   80                               31    100    100     100   100   100   100   80                               32    100    100     20    100   100   100   80                               33    100    100     85    75    100   100   70                               34    100    100     10    100   100   100   80                               35    100    100     50    100   100   100   80                               36    100    100     90    100   100   100   80                               37    100    100     80    100   100   100   80                               38    100    100     100   100   100   100   80                               39    100    100     40    100   100   100   80                               40    100    100     100   100   100   100   80                               41    100    95      80    100   100   100   80                               42    100    95      40    100   100   100   80                               43    100    100     40    60    100   100   80                               ______________________________________                                         A dash (--) indicates that the weed was not tested.                      

Post-Emergence Herbicide Test: This test is conducted in an identicalmanner to the testing procedure for the pre-emergence herbicide test,except the seeds of the seven different weed species are planted 10-12days before treatment. Also, watering of the treated flats is confinedto the soil surface and not to the foliage of the sprouted plants.

The results of the post-emergence herbicide test are reported in TableIII.

                  TABLE III                                                       ______________________________________                                        Post-Emergence Herbicidal Activity                                            Application Rate - 4.48 kg/ha                                                 Cmpd.                                                                         No.   FT     WG      WO    AMG   VL    MD    YNG                              ______________________________________                                        1     20     60      40    60    60    50    80                               2     20     75      70    80    90    85    30                               3     30     10      10    50    85    85    0                                4     100    50      50    50    80    80    30                               5     0      5       30    10    20    50    0                                6     10     0       0     50    80    70    10                               7     70     0       0     50    80    100   60                               8     80     50      50    60    60    80    30                               9     20     60      50    60    60    90    50                               10    100    95      80    30    60    60    80                               11    0      50      5     10    5     30    30                               12    85     85      50    60    70    65    80                               13    80     80      50    50    70    65    70                               14    90     100     90    90    100   100   30                               15    30     80      80    100   100   100   60                               16    60     85      85    90    100   95    30                               17    100    100     80    100   100   100   60                               18    70     100     90    90    100   100   80                               19    10     30      30    90    95    100   0                                20    30     40      70    80    90    100   30                               21    80     80      60    90    80    100   30                               22    50     60      50    90    90    100   30                               23    20     50      50    100   90    100   70                               24    70     80      80    80    80    90    70                               25    10     40      40    60    80    80    30                               26    20     50      40    60    80    60    30                               27    80     80      60    65    80    80    70                               28    30     50      40    80    80    80    30                               29    30     60      40    80    80    80    30                               30    60     80      50    80    80    80    30                               31    85     100     60    100   100   100   80                               32    30     85      20    90    85    100   70                               33    90     80      60    60    80    80    30                               34    80     85      20    90    90    100   30                               35    30     100     30    100   100   100   80                               36    10     90      20    80    95    95    10                               37    30     90      50    80    80    90    30                               38    85     85      60    80    80    80    30                               39    10     60      40    50    60    60    30                               40    50     80      50    80    90    80    80                               41    0      80      50    80    80    80    70                               42    80     90      60    80    80    90    60                               43    30     80      20    80    90    90    60                               ______________________________________                                         A dash (--) indicates that the weed was not tested.                      

The compounds of the present invention and their salts are useful asherbicides and can be applied in a variety of ways at variousconcentrations. In practice, the compounds or salts are formulated intoherbicidal compositions, by admixture, in herbicidally effectiveamounts, with the adjuvants and carriers normally employed forfacilitating the dispersion of active ingredients for agriculturalapplications, recognizing the fact that the formulation and mode ofapplication of a toxicant may affect the activity of the materials in agiven application. Thus, these active herbicidal compounds or salts canbe formulated as granules of relatively large particle size, as wettablepowders, as emulsifiable concentrates, as powdery dusts, as flowables,as solutions or as any of several other known types of formulations,depending upon the desired mode of application. These formulations maycontain as little as about 0.5% to as much as about 95% or more byweight of active ingredient. A herbicidally effective amount dependsupon the nature of the seeds or plants to be controlled and the rate ofapplication varies from about 0.01 to approximately 10 pounds per acre,preferably from about 0.02 to about 4 pounds per acre.

Wettable powders are in the form of finely divided particles whichdisperse readily in water or other dispersants. The wettable powder isultimately applied to the soil either as a dry dust or as a dispersionin water or other liquid. Typical carriers for wettable powders includefuller's earth, kaolin clays, silicas and other readily wet organic orinorganic diluents. Wettable powders normally are prepared to containabout 5% to about 95% of the active ingredient and usually also containa small amount of wetting, dispersing, or emulsifying agent tofacilitate wetting and dispersion.

Emulsifiable concentrates are homogeneous liquid compositions which aredispersable in water or other dispersant, and may consist entirely ofthe active compound or salt with a liquid or solid emulsifying agent, ormay also contain a liquid carrier, such as xylene, heavy aromaticnaphthal, isophorone and other non-volatile organic solvents. Forherbicidal application, these concentrates are dispersed in water orother liquid carrier and normally applied as a spray to the area to betreated. The percentage by weight of the essential active ingredient mayvary according to the manner in which the composition is to be applied,but in general comprises about 0.5% to 95% of active ingredient byweight of the herbicidal composition.

Granular formulations wherein the toxicant is carried on relativelycoarse particles, are usually applied without dilution to the area inwhich suppression of vegetation is desired. Typical carriers forgranular formulation include sand, fuller's earth, attapulgite clay,bentonite clays, montmorillonite clay, vermiculite, perlite and otherorganic or inorganic materials which absorb or which may be coated withthe toxicant. Granular formulations normally are prepared to containabout 5% to about 24% of active ingredients which may includesurface-active agents such heavy aromatic naphthas, kerosene or otherpetroleum fractions, or vegetable oils; and/or stickers such asdestrins, glue or synthetic resins.

Typical wetting, dispersing or emulsifying agents used in agriculturalformulations include, for example, the alkyl and alkylaryl sulfonatesand sulfates and their salts; polyhydric alcohols; polyethoxylatedalcohols; esters and fatty amines; and other types of surface-activeagents, many of which are available in commerce. The surface-activeagent, when used, normally comprises from 0.1% to 15% by weight of theherbicidal composition.

Dusts, which are free-flowing admixtures of the active ingredient withfinely divided solids such as talc, clays, flours and other organic andinorganic solids which act as dispersants and carriers for the toxicant,are useful formulations for soil-incorporating application.

Pastes, which are homogeneous suspensions of a finely divided solidtoxicant in a liquid carrier such as water or oil, are employed forspecific purposes. These formulations normally contain about 5% to about95% of active ingredient by weight, and may also contain small amountsof a wetting, dispersing or emulsifying agent to facilitate dispersion.For application, the pastes are normally diluted and applied as a sprayto the area to be affected.

Other useful formulations for herbicidal applications include simplesolutions of the active ingredient in a dispersant in which it iscompletely soluble at the desired concentration, such as acetone,alkylated naphthalenes, xylene and other organic solvents. Pressurizedsprays, typically aerosols, wherein the active ingredient is dispersedin finely-divided form as a result of vaporization of a low boilingdispersant solvent carrier, such as the Freons, may also be used.

The phytotoxic compositions of this invention can be applied to theplants in the conventional manner. Thus, the dust and liquidcompositions can be applied to the plant by the use of power-dusters,boom and hand sprayers and spray dusters. The compositions can also beapplied from airplanes as a dust or a spray or by rope wick applicationsbecause they are effective in very low dosages. In order to modify orcontrol growth of germinating seeds or emerging seedlings, as a typicalexample, the dust and liquid compositions can be applied to the soilaccording to conventional methods and can be distributed in the soil toa depth of at least 1/2 inch below the soil surface. It is not necessarythat the phytotoxic compositions be mechanically admixed with the soilparticles since these compositions can also be applied merely byspraying or sprinkling the surface of the soil. The phytotoxiccompositions of this invention can also be applied by addition toirrigation water supplied to the field to be treated. This method ofapplication permits the penetration of the compositions into the soil asthe water is absorbed therein. Dust compositions, granular compositionsor liquid formulations applied to the surface of the soil can bedistributed below the surface of the soil by conventional means such asdiscing, dragging or mixing operations. In the following examples theherbicidal compound can be substituted with the herbicidal salt of thecompound.

EMULSIFIABLE CONCENTRATE FORMULATIONS

    ______________________________________                                        General Formula with Ranges                                                                     Specific Formula                                            ______________________________________                                        Herbicidal  5-55      herbicidal compound                                                                          24                                       compound              proprietary blend of                                                                         10                                       surfactant(s)                                                                             5-25      oil-soluble sulfonates                                  solvent(s)  20-90     and polyoxyethylene                                                 100%      ethers                                                                        polar solvent  27                                                             petroleum hydrocarbon                                                                        39                                                                             100%                                    ______________________________________                                    

WETTABLE POWDER FORMULATIONS

    ______________________________________                                        herbicidal   3-90     herbicidal compound                                                                          80                                       compound              sodium dialkyl naph-                                                                         0.5                                      wetting agent                                                                             0.5-2     thalene sulfonate                                       dispersing agent                                                                          1-8       sodium lignosulfonate                                                                        7                                        diluent(s)  8.5-87    attapulgite clay                                                                             12.5                                                 100%                     100%                                     ______________________________________                                    

EXTRUDED GRANULAR FORMULATIONS

    ______________________________________                                        herbicidal  1-20      herbicidal compound                                                                          10                                       compound              lignin sulfonate                                                                              5                                       binding agent                                                                             0-10      calcium carbonate                                                                            85                                       diluent(s)  70-99                     100%                                                100%                                                              ______________________________________                                    

FLOWABLE FORMULATIONS

    ______________________________________                                        herbicidal  20-70     herbicidal compound                                                                          45                                       compound              polyoxyethylene ether                                                                        5                                        surfactant(s)                                                                              1-10     attagel        0.05                                     suspending agent(s)                                                                       0.05-1    propylene glycol                                                                             10                                       antifreeze agent                                                                           1-10     1,2-benzisothiazoline-                                                                       0.03                                     antimicrobial agent                                                                        1-10     3-one                                                   antifoam agent                                                                            0.1-1     silicone defoamer                                                                            0.02                                     solvent      7.95-77.85                                                                             water          39.9                                                 100%                     100%                                     ______________________________________                                    

When salts are used as the active ingredient in the herbicidalcompositions of this invention it is recommended to use salts that areagriculturally acceptable.

The phytotoxic compositions of this invention can also contain otheradditives, for example, fertilizers, other herbicides and otherpesticides, used as adjuvant or in combination with any of theabove-described adjuvants. Fertilizers useful in combination with theactive ingredients include, for example, ammonium nitrate, urea andsuperphosphate.

What is claimed is:
 1. The method of controlling undesirable vegetationcomprising applying to the area where control is desired, anherbicidally effective amount of a compound having the formula ##STR15##wherein R is chlorine, bromine, methyl, methoxy, nitro, trifluoromethyl,or methylsulfonyl;R¹, R², R³ and R⁴ are hydrogen or methyl; R⁵, R⁶, R⁷and R⁸ independently are (1) hydrogen; (2) halogen; (3) C₁ -C₄ alkyl;(4) C₁ -C₄ alkoxy; (5) trifluoromethoxy; (6) cyano; (7) nitro; (8) C₁-C₄ haloalkyl; (9) R^(b) SO_(n) -- wherein n is the integer 0, 1 or 2;and R^(b) is (a) C₁ -C₄ alkyl; (b) C₁ -C₄ alkyl substituted with halogenor cyano; (c) phenyl; or (d) benzyl; (10) --NR^(c) R^(d) wherein R^(c)and R^(d) independently are hydrogen or C₁ -C₄ alkyl; (11) R^(e) C(O)--wherein R^(e) is C₁ -C₄ alkyl or C₁ -C₄ alkoxy; or (12) SO₂ NR^(c) R^(d)wherein R^(c) and R^(d) are as defined; or (13) --N--(R^(c))C(O)R^(d)wherein R^(c) and R^(d) are as defined; and R⁹ is hydrogen or methyl andtheir salts.
 2. The method of claim 1 wherein R⁵, R⁶, R⁷ and R⁸ areindependently are hydrogen; chlorine; fluorine; bromine; methyl; C₁ -C₄alkoxy; trifluoromethoxy; cyano; nitro; trifluoromethyl; R^(b) SO_(n) --wherein n is the integer 0 or 2 and R^(b) is methyl, chloromethyl,trifluoromethyl, ethyl, or n-propyl; R^(e) C(O)-- where R^(e) is C₁ -C₄alkyl; or SO₂ NR^(c) R^(d) wherein R^(c) and R^(d) are as defined in R⁵is in the 3-position and R⁶ and R⁸ are in the 4-position.
 3. The methodof claim 1 wherein R⁵ and R⁷ are hydrogen and R⁶ and R⁸ are hydrogen,chlorine, bromine, fluorine, cyano, trifluoromethyl, or R^(b) SO₂wherein R^(b) is C₁ -C₄ alkyl or C₁ -C₄ haloalkyl.
 4. The method ofclaim 1 wherein R is nitro; R¹ is hydrogen; R² is hydrogen; R³ ishydrogen; R⁴ is hydrogen; R⁵ is hydrogen; R⁶ is 4-chlorine; R⁷ is2-fluorine; R⁸ is hydrogen; and R⁹ is methyl.
 5. The method of claim 1wherein R is nitro; R¹ is hydrogen; R² is hydrogen; R³ is hydrogen; R⁴is hydrogen; R⁵ is hydrogen; R⁶ is 4-chlorine; R⁷ is hydrogen; R⁸ is4-fluorine; and R⁹ is hydrogen.
 6. The method of claim 1 wherein R ischlorine; R¹ is hydrogen; R² is hydrogen; R³ is hydrogen; R⁴ ishydrogen; R⁵ is hydrogen; R⁶ is 4--SO₂ CH₃ ; R⁷ is hydrogen; R⁸ ishydrogen; and R⁹ is hydrogen.
 7. The method of claim 1 wherein R ischlorine; R¹ is hydrogen; R² is hydrogen; R³ is methyl; R⁴ is hydrogen;R⁵ is ydrogen; R⁶ is 4--SO₂ CH₃ ; R⁷ is hydrogen; R⁸ is hydrogen; and R⁹is hydrogen.
 8. The method of claim 1 wherein R is nitro; R¹ ishydrogen; R² is hydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ ishydrogen; R⁶ is 4-chlorine; R⁷ is hydrogen; R⁸ is hydrogen; and R⁹ ishydrogen.
 9. The method of claim 1 wherein R is nitro; R¹ is hydrogen;R² is hydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ is hydrogen; R⁶ is4-trifluoromethyl; R⁷ is hydrogen; R⁸ is hydrogen; and R⁹ is hydrogen.10. The method of claim 1 wherein R is methyl; R¹ is hydrogen; R² ishydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ is hydrogen; R⁶ is 4--SO₂C₂ H₅ ; R⁷ is 2-fluorine; R⁸ is hydrogen; and R⁹ is hydrogen.
 11. Themethod of claim 1 wherein R is nitro; R¹ is hydrogen; R² is hydrogen; R³is hydrogen; R⁴ is hydrogen; R⁵ is hydrogen; R⁶ is 4-trifluoromethyl; R⁷is 2-nitro; R⁸ is hydrogen; and R⁹ is hydrogen.
 12. The method of claim1 wherein R⁵ is hydrogen.
 13. The method of claim 2 wherein R⁵ ishydrogen.
 14. Compounds of the formula ##STR16## wherein R is chlorine,bromine, methyl, methoxy, nitro, trifluoromethyl or methylsulfonyl;R¹,R², R³ and R⁴ are hydrogen or methyl; R⁵, R⁶, R⁷ and R⁸ independentlyare (1) hydrogen; (2) halogen; (3) C₁ -C₄ alkyl; (4) C₁ -C₄ alkoxy; (5)trifluoromethoxy; (6) cyano; (7) nitro; (8) C₁ -C₄ haloalkyl; (9) R^(b)SO_(n) -- wherein n is the integer 0, 1 or 2; and R^(b) is (a) C₁ -C₄alkyl; (b) C₁ -C₄ alkyl substituted with halogen or cyano; (c) phenyl;or (d) benzyl; (10) --NR^(c) R^(d) wherein R^(c) and R^(d) independentlyare hydrogen or C₁ -C₄ alkyl; (11) R^(e) C(O)-- wherein R^(e) is C₁ -C₄alkyl or C₁ -C₄ alkoxy; or (12) SO₂ NR^(c) R^(d) wherein R^(c) and R^(d)are as defined; or (13) --N--(R^(c))C(O)R^(d) wherein R^(c) and R^(d)are as defined; and R⁹ is hydrogen or methyl and their salts.
 15. Thecompounds of claim 14 wherein R⁵, R⁶, R⁷ and R⁸ are independently arehydrogen; chlorine; fluorine; bromine; methyl; C₁ -C₄ alkoxy;trifluoromethoxy; cyano; nitro; trifluoromethyl; R^(b) SO_(n) -- whereinn is the integer 0 or 2 and R^(b) is methyl, chloromethyl,trifluoromethyl; ethyl or n-propyl, R^(e) C(O)-- wherein R^(e) is C₁ -C₄alkyl; or SO₂ NR^(c) R^(d) wherein R^(c) and R^(d) are as defined, andR⁵ is in the 3-position and R⁶ and R⁸ are in the 4-position.
 16. Thecompounds of claim 14 wherein R⁵ and R⁷ are hydrogen and R⁶ and R⁸ arehydrogen, chlorine, bromine, fluorine, cyano, trifluoromethyl or R^(b)SO₂ wherein R^(b) is C₁ -C₄ alkyl or C₁ -C₄ haloalkyl.
 17. The compoundof claim 14 wherein R is nitro; R¹ is hydrogen; R² is hydrogen; R³ ishydrogen; R⁴ is hydrogen; R⁵ is hydrogen; R⁶ is 4-chlorine; R⁷ is2-fluorine; R⁸ is hydrogen; and R⁹ is methyl.
 18. The compound of claim14 wherein R is nitro; R¹ is hydrogen; R² is hydrogen; R³ is hydrogen;R⁴ is hydrogen; R⁵ is hydrogen; R⁶ is 4-chlorine; R⁷ is hydrogen; R⁸ is4-fluorine; and R⁹ is hydrogen.
 19. The compound of claim 14 wherein Ris chlorine; R¹ is hydrogen; R² is hydrogen; R³ is hydrogen; R⁴ ishydrogen; R⁵ is hydrogen; R⁶ is 4--SO₂ CH₃ ; R⁷ is hydrogen; R⁸ ishydrogen; and R⁹ is hydrogen.
 20. The compound of claim 14 wherein R ischlorine; R¹ is hydrogen; R² is hydrogen; R³ is methyl; R⁴ is hydrogen;R⁵ is hydrogen; R⁶ is 4--SO₂ CH₃ ; R⁷ is hydrogen; R⁸ is hydrogen; andR⁹ is hydrogen.
 21. The compound of claim 14 wherein R is nitro; R¹ ishydrogen; R² is hydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ ishydrogen; R⁶ is 4-chlorine; R⁷ is hydrogen; R⁸ is hydrogen; and R⁹ ishydrogen.
 22. The compound of claim 14 wherein R is nitro; R¹ ishydrogen; R² is hydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ ishydrogen; R⁶ is 4-trifluoromethyl; R⁷ is hydrogen; R⁸ is hydrogen; andR⁹ is hydrogen.
 23. The compound of claim 14 wherein R is methyl; R¹ ishydrogen; R² is hydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ ishydrogen; R⁶ is 4--SO₂ C₂ H₅ ; R⁷ is 2-fluorine; R⁸ is hydrogen; and R⁹is hydrogen.
 24. The compound of claim 14 wherein R is nitro; R¹ ishydrogen; R² is hydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ ishydrogen; R⁶ is 4-trifluoromethyl; R⁷ is 2-nitro; R⁸ is hydrogen; and R⁹is hydrogen.
 25. The compounds of claim 14 wherein R⁵ is hydrogen. 26.The compounds of claim 15 wherein R⁵ is hydrogen.
 27. An herbicidalcomposition comprising an herbicidally active 2-(substitutedbenzoyl)-4-(substituted or unsubstituted phenyl)-1,3-cyclohexandionecompound of the formula ##STR17## wherein R is chlorine, bromine,methyl, methoxy, nitro, trifluoromethyl or methylsulfonyl;R¹, R², R³ andR⁴ are hydrogen or methyl; R⁵, R⁶, R⁷ and R⁸ independently are (1)hydrogen; (2) halogen; (3) C₁ -C₄ alkyl; (4) C₁ -C₄ alkoxy; (5)trifluoromethoxy; (6) cyano; (7) nitro; (8) C₁ -C₄ haloalkyl; (9) R^(b)SO_(n) -- wherein n is the integer 0, 1 or 2; and R^(b) is (a) C₁ -C₄alkyl; (b) C₁ -C₄ alkyl substituted with halogen or cyano; (c) phenyl;or (d) benzyl; (10) --NR^(c) R^(d) wherein R^(c) and R^(d) independentlyare hydrogen or C₁ -C₄ alkyl; (11) R^(e) C(O)-- wherein R^(e) is C₁ -C₄alkyl or C₁ -C₄ alkoxy; or (12) SO₂ NR^(c) R^(d) wherein R^(c) and R^(d)are as defined; or (13) --N--(R^(c))C(O)R^(d) wherein R^(c) and R^(d)are as defined; and R⁹ is hydrogen or methyl and their salts and aninert carrier therefor.
 28. The composition of claim 27 wherein R⁵, R⁶,R⁷ and R⁸ are independently are hydrogen; chlorine; fluorine; bromine;methyl; C₁ -C₄ alkoxy; trifluoromethoxy; cyano; nitro; trifluoromethyl;R^(b) SO_(n) -- wherein n is the integer 0 or 2 and R^(b) is methyl,chloromethyl, trifluoromethyl, ethyl, or n-propyl; R^(e) C(O)-- whereR^(e) is C₁ -C₄ alkyl; or SO₂ NR^(c) R^(d) wherein R^(c) and R^(d) areas defined and R⁵ is in the 3-position and R⁶ and R⁸ are in the4-position.
 29. The composition of claim 27 wherein R⁵ and R⁷ arehydrogen and R⁶ and R⁸ are hydrogen, chlorine, bromine, fluorine, cyano,trifluoromethyl or R^(b) SO₂ wherein R^(b) is C₁ -C₄ alkyl or C₁ -C₄haloalkyl.
 30. The composition of claim 27 wherein R is nitro; R¹ ishydrogen; R² is hydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ ishydrogen; R⁶ is 4-chlorine; R⁷ is 2-fluorine; R⁸ is hydrogen; and R⁹ ismethyl.
 31. The composition of claim 27 wherein R is nitro; R¹ ishydrogen; R² is hydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ ishydrogen; R⁶ is 4-chlorine; R⁷ is hydrogen; R⁸ is 4-fluorine; and R⁹ ishydrogen.
 32. The composition of claim 27 wherein R is chlorine; R¹ ishydrogen; R² is hydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ ishydrogen; R⁶ is 4--SO₂ CH₃ ; R⁷ is hydrogen; R⁸ is hydrogen; and R⁹ ishydrogen.
 33. The composition of claim 27 wherein R is chlorine; R¹ ishydrogen; R² is hydrogen; R³ is methyl; R⁴ is hydrogen; R⁵ is hydrogen;R⁶ is 4--SO₂ CH₃ ; R⁷ is hydrogen; R⁸ is hydrogen; and R⁹ is hydrogen.34. The composition of claim 27 wherein R is nitro; R¹ is hydrogen; R²is hydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ is hydrogen; R⁶ is4-chlorine; R⁷ is hydrogen; R⁸ is hydrogen; and R⁹ is hydrogen.
 35. Thecomposition of claim 27 wherein R is nitro; R¹ is hydrogen; R² ishydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ is hydrogen; R⁶ is4-trifluoromethyl; R⁷ is hydrogen; R⁸ is hydrogen; and R⁹ is hydrogen.36. The composition of claim 27 wherein R is methyl; R¹ is hydrogen; R²is hydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ is hydrogen; R⁶ is4--SO₂ C₂ H₅ ; R⁷ is 2-fluorine; R⁸ is hydrogen; and R⁹ is hydrogen. 37.The composition of claim 27 wherein R is nitro; R¹ is hydrogen; R² ishydrogen; R³ is hydrogen; R⁴ is hydrogen; R⁵ is hydrogen; R⁶ is4-trifluoromethyl; R⁷ is 2-nitro; R⁸ is hydrogen; and R⁹ is hydrogen.